How do you know if an element has a close shell or an octet? How do you know if an element has a close shell or an octet? Solution An element is said to have close shell if all the electrons in its valence shell is filled up i.e all electrons should be paired up in order to favour energetically form of element. For example,Chlorine atom has 7 electron in its valence shell so it gains one electron to form Cl - which is energetically more stable and thus form close shell. An element is said to have octet if element has eight electrons in the outermost shell for gaining more stability. For example , NaCl salt in which Na+ and Cl- ions are present .If simply sodium and chlorine are mixed then sodium loses 1 electron and chlorine gains 1 electron thereby making salt stable or unreactive.In this way,having eight electrons or octet in outermost orbit is said to be stable.Though there are many exceptions to it .

1. How do you know if an element has a close shell or an octet?
How do you know if an element has a close shell or an octet?
Solution
An element is said to have close shell if all the electrons in its valence shell is filled up i.e all
electrons should be paired up in order to favour energetically form of element.
For example,Chlorine atom has 7 electron in its valence shell so it gains one electron to
form Cl - which is energetically more stable and thus form close shell.
An element is said to have octet if element has eight electrons in the outermost shell for
gaining more stability.
For example , NaCl salt in which Na+ and Cl- ions are present .If simply sodium and
chlorine are mixed then sodium loses 1 electron and chlorine gains 1 electron thereby
making salt stable or unreactive.In this way,having eight electrons or octet in outermost
orbit is said to be stable.Though there are many exceptions to it